A lot of people pegged Colvin as somebody who was going to bolt for the NFL Draft in the spring coming off a stellar junior season.
He opted to stay. He knew full well the defense was going to be full of young guys who didn't have a lot of experience. He knew full well the other starting cornerback was going to be somebody who didn't even play last season.
It didn't matter. It remains to be seen if this season has hurt or helped his draft status. Frankly, he doesn't really care right now. He knows he has one more regular season game to make one last statement against Bedlam rival Oklahoma State.
"It hasn't really hit me as much yet, but I know it's creeping up on me," Colvin said. "I'm cherishing every moment of it."
Lately the moments haven't been that great for Colvin, who has been battling a nagging shoulder injury throughout most of the second half of the season.
He missed time against Baylor and was able to take the field for senior day against Iowa State. There was no way he was going to miss Kansas State, too, even though he had every reason not to suit up.
"We know that about Slick and his character," redshirt freshman cornerback Zack Sanchez said. "I think it speaks to the people who didn't know about his character. He was out there battling and obviously banged up. He doesn't say much. He just goes out and does it."
This season has been one of injuries for OU. Not just any injuries but debilitating injuries to some of the team's top players. Senior captains Trey Millard and Corey Nelson are both out for the season and have been for a while.
Colvin wasn't about to add his name to that list.
"I felt like I had to play," Colvin said. "I had to be there for my teammates. There were times when it was tough mentally, but we've had too many injuries, too many key injuries. I couldn't be one of those."
Colvin doesn't just symbolize being a leader. He shows it on the field, too. Kansas State wide receiver Tyler Lockett had a career in a half. In the first half last week, Lockett had six catches for 206 yards and three touchdowns.
Shoulder dangling to the side, Colvin accepted the challenge. He had to. The OU coaches said Colvin had to follow Lockett around. It worked as Lockett was limited to six catches for 72 yards in the second half. More importantly, he didn't score or get behind the defense again.
"Aaron gives us confidence, and he gives us some stability in the secondary," OU defensive coordinator Mike Stoops said. "We don't have a lot of experience back there. When he is back there he seems to settle everyone down, and he gives us an outstanding cover guy.
"You are trading a top-level NFL player for someone who hasn't played much so it's pretty evident what you are losing."
Colvin has missed two full games and parts of others but has still been among the most productive defenders on the team. He has 47 tackles with five for loss, an interception, fumble recovery and four pass breakups.
Not surprisingly, teams have looked the other direction. It has helped Sanchez show what he is made of and made him learn on the job.
Sanchez had a rough first half against Lockett, but Colvin was among the first to talk to him at halftime and told him to shake it off and keep moving forward.
That leadership hasn't gone unnoticed.
"It's just been an uncomfortable season for him with his shoulder," Stoops said. "He has really toughed it out and that says a lot about his character and his toughness. He's just a fighter, and I'm sure he'll want to play a great game here in a couple of weeks."
And a great Bedlam game starts with practices this week and next week. Colvin knows he is expected to set the tone, and he's fine with that.
"Usually what happens on Saturday is what happens at practice that week," Colvin said. "You have to tell those young guys to pick up their stuff sometimes and get a little more serious, but these guys get it. These guys had to mature very quickly this year, so there's not too much that needs to be said to them."